Delay network



Sept. 2, 1958 R. WIDMER DELAY NETWORK.

Filed March '7, 1955 INVENTOR. RUDOLF WIDMER BY x21 Qumrm sssas 6 30? Y?5555 a aosv znc b csnsv aa an-In a:

I QUANTITY SHIPPED C! D D ONE CYCLE POINT 1 United States {Patent ODELAY NETWORK Rudolf Widmer, Stuttgart, Germany, assignor toInternational Business Machines Corporation, New York, N. Y., acorporation of New York Application March 7, 1955, Serial No. 492,342Claims priority, application Germany March 31, 1954 I 4 Claims. (Cl.315-166) This invention relates to a machine for perforating recordcards, and, more particularly to a perforating machine, wherein,differentially positioned conductive marks are sensed on successiverecord cards at one time interval for effecting the punching ofperforations thereon in positions corresponding to the sensed conductivemarks at another time interval.

In mark sensing devices pencil marks ofconductive material (e. g. highgraphite content lead) which were previously applied on a recordmaterial are electrically sensed by contact brushes, after which thesensed data is punched in some desired column of the card. In suchdevices, three contact brushes per card column are used, the two outerbrushes being connected together and to a power source and the centralbrush being insulated from the other two brushes. During the passage ofcards through the sensing station, the presence of a suitable markelectrically connects either or both of the outer brushes with thecentral brush and develops a pulse for operating a punch magnet at thepunch station. However, since it is desired to punch this sensedinformation in the same card, the mark sensing pulse must be delayeduntil the corresponding column of the card is below the punch magnet. Amark sensing and punching device of this character is disclosed in U. S.Patent Nos. 2,007,391, 2,275,396 and Reissue Patent No. 21,133.

In the disclosed mark sensing and punching arrangement 1 /2 cycle pointsseparate the mark sensing brush location from the punch station. Sinceeach mark location on the card is /2 cycle point above the correspondinghole location, this means that two cycle point delay (equivalent toapproximately 80 milliseconds) is necessary from the time a mark issensed until a punch should operate. In the invention disclosed inPatent No. 2,275,396 this needed delay is accomplished by a rotary typeof data storage means, which is operated in synchronism with the recordcard feeding mechanism.

The present invention is an improved delay means which is capable ofdelaying the sensed pulse for the required time interval prior tooperating the punch magnet. The delay means is composed 'of a group ofmechanical and electronic components whose synchronized operationproduces the required two cycle point delay. As one pair of cam contactscloses each time that a mark on a moving card is sensed at the sensingstation, the pulse developed energizes an electronic circuit whichoperates in conjunction with other cam contacts to energize thecorresponding punch magnet to accomplish the desired punching operation.

Accordingly, the principal object of the present invention is to providean improved delay means between the sensing station and the punchstation in a record controlled perforating machine.

Another object is to provide an efficient delay means which is capableof compensating in time for the physical distance between the sensingstation and the punch station and between the mark location and thecorresponding hole location on the card.

Other objects of the invention will be pointed out in v trolledperforating machine showing the feeding, sensing 2. the followingdescription and claims and illustrated in the accompanying drawingswhich disclose, by way of example, the principle of the invention andthe best mode which has been contemplated of applying that principle.

In the drawings: Fig. 1 is a sectional elevation view of a record conandperforating devices.

Fig. 2 is a detailed view showing a portion of the record card.

Fig. 3 is a schematic diagram of the invention.

In Fig. 1 is shown the essential elements of the card controlledperforating machine disclosed in Reissue Patent No. 21,133 referred tohereinabove. Only that part of the machine containing the mark sensingand perforating mechanism is illustrated. In brieflyexplaining theoperation of this part of the machine, the same reference characters areemployed as in this patent to facilitate the description thereof.

The record cards containing the conductive marks are placed in hopper P,and are fed individually by oscillating arm 83, reciprocating slide 84,and picker knife to the feed rollers 103 and 104, The individual cardsare then fed by the said feed rollers past a mark sensing station, whichis disposed ahead of the punching station. The mark sensing station iscomposed of the sensing brush assembly 601, which contains a pluralityof spaced sets of stranded wires 603 in an insulating member .604, andan insulating bar 602. The said sensing brushes are arranged withrespect to the punching station so that the mark positions on the cardsare sensed two cycle points before the corresponding mark positionssensed are fed to the punching station.

The delay circuit of Fig. 3 is controlled by a set of said sensingbrushes 603, upon sensing the conductive marks, for storing the senseddata for two machine cycle points. At the end of this time interval, asthe card is moved into the punch station the delay circuit effects theenergization .of the related punch magnet PM to perforate the card inthe positions corresponding to the sensed marks. One such delay circuitis provided between each set (three wires) of brushes 603 and a par-vticular punch magnet PM.

Energization of said magnet PM rocks its armature structure 190, drawinga link 192 to the right, to effect coupling between an interposer 186and a plate 184. The plate 184 is carried by member 177 pivoted at 183and oscillated by means of a link 178 connected to an arm 176 onshaft175. The desired punch 13 is brought down into die 167 when theassociated interposer 136 is coupled to plate 184. .Rollers 105 and 106then convey the punched card to the usual stacker.

Referring to Fig. 2, there is shown a partial card with conductive marksin index positions 3, 9 and 5, indicating that 395 is the quantity ofthe item identified by the card. It will be noted that the markingpositions for the conductive marks are located above the correspondingpunch positions, for. example, the 3 marking position is located betweenthe 2 and 3 punch positions. Stated another way, the marking position is/2 cycle point removed from the corresponding punch posi: tion.

' Fig. 3' illustrates schematically the circuit which delays each pulsedeveloped by a conductive mark sensed by a set ofrbrushes 603 beforeoperating the corresponding magnet PM. In this figure, one set ofbrushes 603 is shown in exaggerated form making contact with one colmumof a card 11. The two outer wires or brushes 603 are connected togetherat juncture 2, and through a resistor 3 they are normally connected to a-25 volt source.

When cam4 closes its contacts 4A, the outer brushes 603 also becomeconnected to the volt source.

The inner brush 603 is insulated from the two outer brushes 603 and isin electrical contact with said outer brushes only when a conductivemark is sensed on a card. Inner brush 603 is connected through resistor5 to a-25 volt supply and through current limiting resistor 6 to thecontrol grid of gaseous tube 7. The control grid is thus normally atnegative potential and non-conductive, and becomes conductive only whenthe central brush 603 is in electrical contact with either or both outerbrushes 603 through a conductive mark on a card 11.

Between the control grid of tube 7 and the cathode and the screen grid,which are tied together, is capacitor 8. When cam 9 closes its contacts9A, the cathode and screen grid of tube 7 are connected directly to the0 volt source. The cathode and screen grid are also connected throughresistor 10 to the +125 volt source. Thus Whenthe contacts of earn 9 areopen, the cathode of tube 7 is at the same potential as the control gridand the tube cannot conduct. When no mark is sensed by brushes 603, thecontrol grid is more negative than the cathode regardless Whether or notcam contacts 9A are closed. Only when a mark is sensed simultaneouslywith the closure of contacts 4A and 9A will the proper voltagedifferential exist between the control grid and cathode of tube 7 tofire said tube. The anode of tube 7 is connected through resistor 21 tothe +125 volt supply.

The anode of tube 7 is also connected through capacitor 12 and resistor13 to the control grid of gaseous tube 14. In its normal condition thecontrol grid of tube 14 is negatively biased by resistor 15 which isconnected to the 25 volt source. As in the case of tube 7, the controlgrid is connected through a capacitor 16 to the cathode of tube 14. Thecathode of tube 14 is connected through punch magnet PM to the 0 voltline, said punch magnet being energized only when tube 14 issufliciently conductive.

A form of coincidence arrangement is employed to control the operationof tube 14. The anode of tube 14 is connected to the +55 volt line onlywhen cam 17 closes its contacts. The screen grid is connected throughresistor 18 to the 25 volt source, and, when cam 19 closes its contacts,also through resistor 20 to the +55 volt source. Tube 14 conductssufficiently to operate magnet PM only when cam 17 closes its twocontacts.

The rotation of cams 4, 9, 17 Y and 19 is synchronized with the movementof the cards 11, since the cams are mounted on the card advance shaft(not shown). The cams are also synchronized in relation to each other ina manner to provide the required two cycle point delay, as is describedbelow.

In operation, cam contacts 4A are closed each time brushes 603 are at anindex point position. In the absence of a mark on the particularposition being sensed, only the two outer brushes 603 will be at apositive potential. The inner brush 603, being insulated from the twoouter brushes, will remain at a negative potential and tube 7 will notconduct at this time.

However, as soon as a conductive mark is sensed, the three brushes areelectrically connected to the +125 volt source and the control grid oftube 7 is made positive. The closure of contacts 9A now makes thecathode more negative than the control grid and so the tube fires.Conduction will continue during the period of closure of cam contacts 4Aand 9A. The voltage drop across anode resistor 21 developed at this timeis coupled through capacitor 12 to the control grid of tube 14 and makesthe control grid more strongly negative than the normal 25 voltsprovided by resistor 15. This means that when tube 7 is conductive, tube14 must be non-conductive.

As cam 9 continues its rotation to open its contacts, tube 7 no longerconducts, and the potential at the lower end of resistor 21 approachesits maximum level of +125 volts. As a result, the control grid of tube14 becomes sufficiently positive for conduction. Before cam contacts 9Aopen, cam 19 closes its contacts, which action makes the screen grid oftube 14 positive. This causes tube 14 to conduct but not sufiiciently toenergize punch magnet PM. Immediately after contacts 19A are closed,earn 17 closes its contacts to connect the anode of tube 14 to the +55volt supply. With contacts 19A and 17A closed simultaneously the maximumcurrent flows through tube 14, operating punch magnet PM, which rocksits armature structure (see Fig. 1) to effect coupling betweeninterposer 186 and plate 184 for accomplishing a perforation of themoving card.

The cams are so synchronized with the card movement that punch magnet PMis energized just as the card presents its punch position to punch 18.In this way the time consumed between the energization of punch magnetPM and the lowering of punch element 18 is taken into consideration.

While there have been shown and described and pointed out thefundamental novel features of the invention as applied to a preferredembodiment, it will be understood that various omissions andsubstitutions and changes in the form and details of the deviceillustrated and in its operation may be made by those skilled in theart, without departing from the spirit of the invention. It is theintention, therefore, to be limited only as indicated by the scope ofthe following claims.

What is claimed is:

1. A delay net work adapted for use in record card controlled machinesto delay the signal effect of an input pulse, comprising a first andsecond pair of cam contacts, a first gas discharge device, said firstand second pair of contacts making the first discharge device conductiveat one time interval when an input pulse is applied to said firstdischarge device, a third and fourth pair of cam contacts synchronizedto operate with said first and second pair of cam contacts, a second gasdischarge device, said second pair of contacts extinguishing said firstdischarge device and making the control grid of said second dischargedevice positive, said third pair of cam contacts applying a positivepotential to the screen grid of said second discharge device, thepositive condition of both grids being capable of firing said seconddischarge device, and said fourth pair of cam contacts applying apositive potential to the anode of said second discharge device, to makesaid second discharge device fully conductive in order to energize anoutput device.

2. The invention according to claim 1, wherein said first and secondpair of contacts close simultaneously at a predetermined point of eachoperating cycle, said third pair of contacts close before said secondpair of contacts open, and said fourth pair of contacts close after saidthird pair of contacts have closed.

3. The invention according to claim 2, wherein a resistor connectedbetween said third pair of cam contacts and said second discharge deviceconnects the screen grid of said second discharge device to a positivesource whenever said third pair of contacts close thereby causing saidsecond discharge device to fire but not to conduct sufliciently toenergize an output device.

4. The invention according to claim 3 in which said screen grid currentlimiting resistor is part of a voltage divider.

References Cited in the file of this patent UNITED STATES PATENTS2,056,301 Schroter Oct. 6, 1937 2,228,883 Morgan Jan. 14, 1941 2,249,819Gulliksen July 22, 1941 2,260,039 Leroy Oct. 21, 1941 2,264,621 Cox Dec.2, 1941 2,275,396 Johnson Mar. 3, 1942 2,306,404 Potts Dec. 29, 19422,419,601 Silver Apr. 29, 1947 2,649,502 Odell Aug. 18, 1953

